Omron E5CZ User Manual page 136

Adjustment Level
p
Proportional Band
i
Integral Time
d
Derivative Time
Function
Parameters
Proportional
band
Setting
Integral time
Derivative time
See
See
c-sc
Cooling Coefficient
Function
Setting
These parameters set PID control constants. PID constants are automatically
set when AT or ST is executed.
P action: Refers to control in which the MV is proportional to the deviation
(control error).
I action: Refers to a control action that is proportional to the time integral of
the deviation. With proportional control, there is normally an offset
(control error). Proportional action is thus used in combination with
integral action. As time passes, this control error disappears, and
the control temperature (process value) comes to agree with the set
point.
D action: Refers to a control action that is proportional to the time derivative
of the control error. The proportional control and integral control cor-
rect for errors in the control result, and thus the control system is
late in responding to sudden changes in temperature. The deriva-
tive action increases the MV in proportion to the slope of the change
in the temperature as a corrective action.
Models
Controllers with Thermocouple/
Resistance Thermometer Univer-
sal-inputs
Controllers with Analog Inputs
Note Set "none" as the unit for Controllers with Analog Inputs.
Related Parameters
AT execute/cancel (adjustment level): Page 108
If the heating characteristics and cooling characteristics of the control object
are very different and good control characteristics cannot be achieved with
the same PID constants, the cooling coefficient can be used to adjust the pro-
portional band (P) for the control output assigned to the cooling side.
In heating/cooling control, the proportional band P for the cooling control out-
put is calculated using the following formula to set the cooling coefficient:
Cooling control output side P = Cooling coefficient × P (proportional band)
Setting range
0.01 to 99.99
Setting range
0.1 to 999.9
0 to 3999
0 to 3999
Unit Default
None 1.00
Section 5-4
The control must be set to 2-PID
control.
Unit
°C or °F
8.0
(See note. )
%FS 10.0
Second 233
Second 40
The control must be heating/cooling
control and 2-PID control.
Default
113